"After a careful review of the crime, evidence, and interviews, it was determined that adult charges against Mr. Cano were warranted," State Attorney's Office spokesman Mark Cox wrote in an e-mail.

On Aug. 16, police received a tip that former student Jared Cano was planning to bomb Freedom the first day of school. The informer said Cano planned to target two faculty members and nearby students, police reported.

When officers searched Cano's bedroom at his mother's New Tampa apartment, they found ingredients to build pipe bombs, schematics for Freedom and a journal that explained plans to kill even more people than the 13 massacred in 1999 at Columbine High, the department said.

Police Chief Jane Castor said officers thwarted a "catastrophic event the likes of which Tampa has not seen."